Generating retinal flow maps from structural optical coherence tomography with artificial intelligence

TL;DR

This paper presents an AI method that generates detailed retinal vasculature maps from standard OCT images, surpassing expert accuracy and enabling broader use of existing OCT data without specialized hardware.

Contribution

The study introduces a deep learning model that infers retinal microvasculature perfusion from structural OCT images, eliminating the need for OCTA and expert labels, thus expanding clinical and research applications.

Findings

AI-generated vasculature maps match OCTA fidelity

Model outperforms expert clinicians in accuracy

Enables use of standard OCT data for vascular imaging

Abstract

Despite significant advances in artificial intelligence (AI) for computer vision, its application in medical imaging has been limited by the burden and limits of expert-generated labels. We used images from optical coherence tomography angiography (OCTA), a relatively new imaging modality that measures perfusion of the retinal vasculature, to train an AI algorithm to generate vasculature maps from standard structural optical coherence tomography (OCT) images of the same retinae, both exceeding the ability and bypassing the need for expert labeling. Deep learning was able to infer perfusion of microvasculature from structural OCT images with similar fidelity to OCTA and significantly better than expert clinicians (P < 0.00001). OCTA suffers from need of specialized hardware, laborious acquisition protocols, and motion artifacts; whereas our model works directly from standard OCT which are ubiquitous and quick to obtain, and allows unlocking of large volumes of previously collected standard OCT data both in existing clinical trials and clinical practice. This finding demonstrates a novel application of AI to medical imaging, whereby subtle regularities between different modalities are used to image the same body part and AI is used to generate detailed and accurate inferences of tissue function from structure imaging.